Titanium metal is primarily employed in the field of aircraft, and there is a tendency for demand for titanium material to increase because of increase in demand to replace aircraft. In addition, there also is a tendency of increased demand for titanium material for consumer use. Thus, it is necessary to satisfy the demands for titanium material worldwide.
Under such circumstances, supply of rutile and ilmenite, which are ores as raw materials for the production of titanium metal, has not been sufficient, and improvement in the situation is required.
On the other hand, when focusing on scrap generated after processing of titanium metal ingots, although the material remaining after processing of titanium material of a final product has been individually traded and recycled, titanium metal scraps are merely recycled among all of the titanium metal scraps generated in the entire market. Thus, enlargement of titanium scrap recycle is required from the viewpoint of resource conservation.
An ingot produced by ingot melters (one who produces ingots from new raw material or recycled raw material and supplies ingots, hereinafter simply referred to as a “maker”) is supplied to ingot users for machining or plastic deformation (one who produces half-finished product or final product by processing the ingot supplied, hereinafter simply referred to as a “user”), the ingot is processed so as to produce ingot at ingot user factory, and the scrap remained as a byproducts at the same time. This kind of scrap is recovered and returned to ingot melters again.
The titanium scraps which are recycled from ingot users to ingot melters are classified as so-called CP scrap and alloy scrap by sorting operation between CP scrap and alloy scrap, thereof is performed manually, and it is necessary to analyze alloy compositions for each scrap. Thus, there is a room for improving the sorting efficiency.
Furthermore, there are possibilities of mistakes in the manual sorting of titanium scrap and mistakes in re-melting ingots using erroneously sorted scrap as a raw material, and thus there is room for improvement from the viewpoint of guarantee of quality of the ingot.
To solve the problems, a method has been suggested in which an IC tag recording product information thereof is attached to a resin product to be recycled (See the Patent Publications 1 to 3 below).
In this method, individual information for identification of the resin in recycling materials is recorded in the IC tag. Therefore, by reading the individual information for identification of the IC tag recorded to the recycled material, properties of the recycled material can be understood, and as a result, the resin product can be efficiently reproduced (See the Patent Publication 1).
However, in a case that an ingot as a product is melted and produced, it is necessary that titanium material such as titanium sponge and additives such as titanium oxide and iron oxide be mixed in addition to the titanium scrap recycled so as to satisfy compositions of the product ingot. It is not difficult to efficiently produce ingots having high quality required by the market, merely by giving the IC tag to recycled titanium, identifying the features of the raw material that is recycled, and recycling according to the method disclosed in the Patent Publication 1.
As noted above, in order to satisfy the quality of the ingot required as a product, a system is required, in which kinds and amounts of the additives added to the titanium scrap are appropriately set and the feed rate of each additive is controlled in consideration of feeding rate of the titanium scrap, in addition to selection of the titanium scrap.
The Patent Publications are as follows.    1: Japanese Unexamined Patent Application Publication No. 2002-370257    2: Japanese Unexamined Patent Application Publication No. 2009-245298    3: Japanese Unexamined Patent Application Publication No. 2005-067850